Subpena

A writ commanding the attendance in court, as a witness, of the person on whom it is served, under a penalty; the process by which a defendant in equity is commanded to appear and answer the plaintiff's bill.

Subpena ad testificandum (). [NL.] A writ used to procure the attendance of a witness for the purpose of testifying. -- Subpena duces tecum (). [NL.] A writ which requires a witness to attend and bring certain documents.